Aerating stirrer



Sept. 5, 1933. Q sp 1,925,777

AERATING STIRRER Filed Jan. 14, 1932 Jrmentor Usaap 5 srlz'n mmM attorney Patented Sept. 5, 1933 PATENT OFFICE,

1,925,777 AERATING STIRRER Oscar Sperling, Washington, D. 0., assignor of twenty-five per cent to Fred A. Carter and twenty-five per cent to James A. Saunders, beth of Washington, D. C.

Application January 14, 1932. Serial No. 586,666 4 Claims. (01. 261-87) This invention relates to aerating stirrers and has for its general object the provision of a rotary agitator for mixing and at the same time aerating drinks, foodstuifs and fluid ingredients of foodstuffs as for example, batter. 7

Another object of the invention is the provisio of a motordriven food or fluid mixer comprising a hollow rotary shaft having a stirring element extending in a plane substantially perpendicular to the rotation of the shaft andso constructed as to generate a current of air by centrifugal force and inject the air in finely divided streams of bubbles into the mass of the drink orfoodstuff in the region of the stirring element, whereby air is incorporated into the fluid during the mixing or stirring of the latter, lightening it, increasing its bulk, and giving it those advantageous properties of aeration which characterize whipped cream or beaten egg whites, etc.

Another object of the invention is to provide the stirrer with air drawing means at its submerged end and air forcing means in an exposed portion, both cooperating under centrifugal force to drive a positive stream of air through thestirrer and into the food or drink being stirred.

Still another object of the invention is to provide quick detachable air impeller or scoop on the shaft in the zone of the air inlet, which scoop can be removed for cleansing.

Other objects of the invention reside in the specific construction of the stirring element, the protective hood extension of the motor casing which encompasses the air scoop, and in the, demountability of the several parts.

In the drawing which accompanies and forms a part of the following specification and throughout the several figures of which, the same reference characters designating identical parts:

Figure 1 is a perspective view of the aerating stirrer;

Figure 2 is a similar view, the upper part being broken away and the lower part being shown in section;

Figure 3 is a section taken along the line 3-3 of Figure 2; V

Figure 4 is a section taken along the line 4-4 of Figure 3;

Figure 5 is a cross section taken along the line 55 of Figure 2; and

Figure 6 is a perspective view of the detachable air scoop.

Referring now in detail to the several figures, the numeral 1 represents an electric motor, the casing of which is made relatively long and narrow so as to serve as a handle. The projecting end 2 of the motor shaft serves as a means for the attachment of the shaft 3 of the stirrer which is preferably tubular and slotted at its upper end as shown at 4 to impart resiliency through which it may bespread so as to frictionally embrace the projecting end 2 of the motor and to be driven thereby. The lower end also of the shaft 3 is slotted so that it may be pressed into sticking relation into the socket 5 formed in the stirring element or button 6. The latter has preferably the form of a cylindrical disk '7 and formed with radial apertures 8 communicating by way of the socket 5 with the bore of the shaft 3. Said shaft is provided at points remote from the stirring button with airinlet slots 9 and 10.

Centrifugal force in the radial apertures 8, in-

duced by the rapid rotation of the shaft 3 forces the air in said apertures radially outward and 'slots 9 and 10 and under the rapid rotation of the shaft 3 force air into the airinlets. A small hole 15 may be drilled or otherwise formed in the shaft 3, and the attachment 11 provided with a punched indentation 16 adapted to snap into the hole 15, thus securing the attachment in place.

The motor casing is provided with a hood 17 protectively surrounding the air scoops 13 and 14 preventing the possibilityof injury to the user and of damage tothe air scoops while the device is rotating. The hood may be provided with an opening 18 of relatively large diameter both for the purpose of admitting air to the hood and to facilitate aligning the shaft 3 with the end of the motor shaft in attaching the shaft 3 to the motor. The hood may also be provided with additional perforations19 to avoid restricting the volume of admitted air.

The stirring button 6 is preferably formed of circular curvature, and provided at points intermediate the orifices of the apertures 8 with indentations 30, the edges of which take hold of the substance to be agitated and enhance the efiiciency of the stirring.

The outer ends of the radial apertures 8 are formed with pockets 21, each having an abrupt shoulder 22 facing away from the direction of rotation of the stirrer. This pocket has the effect of presenting anextended area of air under pressure of the centrifugal force, to the surrounding liquid medium in the rotation of the device, thereby entraining the air with the liquid in the form of a fine stream or streams of bubbles.

The stirring button is also provided with aplurality of passages 23 extending therethrough,

opening in the upper and lower faces'of said button. Said passages permit the flow therethrough by displacement of viscous masses such as batter when the stirrer is thrust into said masses facilitating the complete submergence of the stirrer button and ensuring the imprisoning of the injected air.

Referring particularly to Figure 2, it will be understood that the stirring button 6 is frictionally fitted to the shaft 3 and may be-removed'therefrom at any time for a thorough cleansing, although-ordinarily, no such cleansingis required since centrifugal force prevents: the liquid or other fluid in which the stirrer is immersed from entering the air passages. Likewise, the shaft 3 may be readily detached from'the projecting end of the motor shaft. This is accomplished by first removing the two screws 24 permitting the hood 1"! to be separated from the casing of the motor.

Attachment 11 may then-be slipped endwise from the shaft and the shaft drawn out through the aperture 18 in the bottom of the hood. The parts thus separated maybe subjected to a complete process of sterilization.

While I have in the-above description disclosed what I believe to be a preferred and practicalembodiment of the invention, it is to :be understood that the details of I construction as shown are merely byway of example and not to be-construed as limiting the scope of the invention as claimed. 1 f i a What I claim is:

1. Electric aerating stirrer comprising a motor functioning as a handle, a hollow shaft attached 7 to the rotor shaft of said motor, an agitating element at the free end of said shaft having radial apertures communicating with the bore of said shaft and opening substantially peripherally, said shaft having an air inlet above the point to which the stirrer is adapted to be immersed, cupped vanes on said shaft in the zone of said air inlet for forcing air into said shaft, and a perfo- Jrated guard secured to said motor and surrounding said cupped vanes.

2:. Electric aerating stirrer comprising a motor functioning as ahandle, a hollow shaft attach'ed to the rotor shaft of said motor, an agitating element at the free end of said shaft having 'radialaperturescommunicating with the bore of said shaft and opening substantially periphorally, said shaft having an air inlet above the '2, with interengagin'g means on said shaft and clip respectively for definitely positioning said resilient means;

4. Electricaerating stirrer comprising a motor having a rotor shaft, said motor functioning as a handle, a guard secured to the motor, a hollow shaft, an agitating element on one end of the 'h'ollow shaft, a frictionalislip joint connection between the other end of the hollow shaft and the rotorishaft within the perforated guard and means on the hollow shaft within the perforated guard for forcing air through said shaft to the agitator element.

OSCAR sPERL ING. 

